Okay, how about this approach. I need to control 4 - 24Vac devices, 8 - 110Vac devices, a 24 Vac stepper motor, monitor 1 temp sensor and a couple of digital inputs via a 485 MKR Shield and I assume a MKR Zero. I realize this may take more than one relay driver arrangement PCB connected to the MKR Zero. I was looking at a Arduino MKR Motor Carrier to create an interface to the AC relays. Is this a reasonable approach? Might there be better options for the relay and driver boards needed that can connect to the MKR Zero?
I have no problem designing the actual driver PCB but would like a good interface option to that PCB.